Magnetically operated multi-valve assembly



May 13, 1969 R. H. REINICKE MAGNETICALLY OPERATED MULTI-VALVE ASSEMBLYSheet of2 Filed July 5, 1967 INVENTOR. ROBERT A! PE/N/CKE y 3, 1969 R.H. REINICKEQ 3,443,585

MAGNETICALLY OPERATED MULTI-VALVE ASSEMBLY Filed July 5, 1967 Sheet 8 of2 F/E, E

NVEN'TOR.

United States Patent 3,443,585 MAGNETICALLY OPERATED MULTI-VALVEASSEMBLY Robert H. Reinicke, Thousand Oaks, Calif., assignor to NorthAmerican Rockwell Corporation, a corporation of Delaware Filed July 3,1967, Ser. No. 650,693 Int. Cl. F161; 31/02 US. Cl. 137595 14 ClaimsABSTRACT OF THE DISCLOSURE A multi-valve assembly having at least twoball shaped valves made of magnetizable material that act as armatures.The valves are included in a magnetic circuit which operates, withoutthe aid of mechanical guides, dynamic seals or the like, tosubstantially simultaneously move the balls along substantially straightpaths between their valve-closed and valve-opened positions.Valve-opened and valve-closed positions are maintained solely bymagnetic forces, therebyeliminating the need for mechanical springs,detents or the like.

Background of the invention This invention relates to electrical valveactuators and more specifically to a magnetic circuit for interlinkingand substantially simultaneously actuating multiple valves. The use ofsolenoid coils in conjunction with electromagnetic plungers or armaturesfor regulating valve motion is well established in the prior art. Whenindividual solenoids are used to operate a plurality of valves, itbecomes diflicult to precisely regulate the valves simultaneously.Although the solenoids may be hooked up in the same electrical circuit,there is always the risk of an inductive lag timing mismatch that willresult in variable rather than simultaneous valve motions. The numerousand complex components of conventional circuits, as well as theiroverall cost and required packaging space, renders the circuitimpracticable and undesirable for many uses.

Although the use of single magnetic circuits for incorporating andactuating dual valves are known (e.g., British Patent No. 21,824, 1914),they are incapable of reliably producing substantially simultaneousmovements of the valves. This inability arises in part because, unlikein the case of the instant invention, the valves in the conventionalcircuits are not magnetically interlinked within a commonelectromagnetic circuit and therefore movement of one valve exerts onlyminimal if any influence on the other valves. Another problem sourceimpairing the reliability of conventional dual valve assemblies residesin the extensive use of coupling the valve with components such asmechanical springs, dynamic seals, sliding fits, flexures and the like.The risk of developing defects is greatly increased by vibration, shock,temperature cycling, contamination, fatigue, etc. The instant inventioncompletely eliminates using these types of components. A direct benefitderived from eliminating these components is that the mass of the movingparts is substantially diminished and therefore much faster valveresponse periods are obtainable.

Summary of the invention Briefly stated, the instant inventioncontemplates a multiple valve assembly including at least two valves,each being constructed of magnetizable material. The valves serve asarmatures and are arranged in a magnetic circuit which magneticallyinterlinks the valves so that movements of one valve automaticallyinfluences the motion of the other valve with the result that the valvesmove substantially simultaneously. The magnetic circuit includes a firstC-shaped electromagnet and a second C- shaped electromagnet which arespaced from and open toward one another. The free ends of the arms ofthe C-shaped electromagnets serve as pole faces and are spaced apartsufiicient to constitute a pair of spaces in which the valves areretained. A permanent magnet is disposed between the two electromagnetsand is formed at its opposing ends with circular openings thatcircumscribe the valves. The magnetic circuit diverts magnetic fluxgenerated by the permanent magnet from one electromagnet to the other inorder to move the valves between their valve-opened and valve-closedpositions.

In accordance with one embodiment of this invention energizing theelectromagnets magnetically urge the valves from either theirvalve-opened or valve-closed position to their other position and uponde-energization the valves remain in their latter position. In order toreturn the valves to their original position, the magnetic circuit isenergized under reversed electrical polarity conditions. According toanother embodiment of this invention, the valves are moved from one oftheir positions to their other positions by energizing theelectromagnets, however, upon de-energization the valves automaticallyreturn to their original positions and hence energization under reversepolarity conditions is dispensed with. In the latter case the valves arepositioned so that upon de-energization the magnetic forces urging thevalves to their original positions exceed those tending to retain thevalves.

The two electromagnets and the permanent magnet are rigidly heldtogether by a supporting framework which assures that none of the valveassembly components other than the valves will be movable. In anotheraspect of this invention, fluid inlet passageways are formed through thearms of one electromagnet and are positioned to be adjacent with fluidoutlet passageways formed through the arms of the other electromagnet.The inlet and outlet passageways both communicate with the spaces thatoccupy the valves so that when the valves are in their valveopenedpositions a pair of independent and continuous fluid lines are created.Potential failure sources in the valve assembly are substantiallyminimized in that the valve assembly does not utilize mechanicalsprings, guides, sliding fits, dynamic seals, flexures, etc. Thisinvention also comprehends moving a single valve along a straight pathbetween its valve-opened and valve-closed positions under the magneticforces generated by the magnetic circuit described above.

Brief description of the drawings The advantages of the instantinvention will be clearly understood upon studying the followingdetailed description in conjunction with the detailed drawings in which:

FIG. 1 is a longitudinal, cross-sectional view through .a valve assemblyformed in accordance with one embodiment of the instant invention,showing a magnetic circuit incorporating a pair of spherical valves thatserve as armatures;

FIG. 2 is slightly modified perspective view of the valve assemblydepicted in FIG. 1 with sections removed from some of its components;

FIG. 3 is an enlarged fragmentary view of the permanent magnet depictedin FIGS. 1 and 2, showing circular openings in which the valves aredisposed;

FIG. 4 is a cross-sectional view of a portion of another valve assembly;

FIG. 5 is a schematic view depicting the relative magnetic fluxquantities in two flux loops of the magnetic circuit when the valves arein their valve-closed positions;

FIG. 6 schematically represents the relative magnetic flux quantities inthe two flux loops of the magnetic circuit when the valves are in theirvalve-opened positions.

Description of the preferred embodiments Referring now to one embodimentof this invention, FIG. 1 is a sectional view showing the essentialcomponents of a dual valve assembly 10 designed to simultaneouslycontrol the flow of fluid through two separated fluid lines. Valveassembly 10 incorporates a C-shaped electromagnetic core 12 whosecentral section 14 is encircled by a solenoid coil 16. Arms 19 and 21 ofcore 12 are identically formed with fluid inlet passageways 22, each ofwhich terminates in a comically-shaped port 23 that extends into anannular passageway 24. Alternatively each port 23 could be a pluralityof diverging apertures. Integrally formed at the free ends of arms 19and 21, respectively, are plugs 25 and 27 which are of reduced diameterand, in part, are shaped by ports 23 and annular passageways 24.Terminal walls 28 and 29 of plugs 25 and 27, respectively, arespherically shaped and serve as magnetic pole faces as will be fullyexplained below. Valve assembly 10 includes another electromagnetic C-shaped core 32 whose central section 34 is encircled by a solenoid coil36. Extending centrally through arms 39 and 41 of core 32 are fluidoutlet passageways 42. Electromagnets 12 and 32 open toward one anotherwith adjacent arms separated to constitute spaces. As will be explainedthe spaces retain valves. The free ends of arms 39 and 41 terminate inspherically shaped walls 46 and 47 which, as will be fully explained,serve as valve seats and magnetic pole faces. Zones of pole faces 46 and47 surrounding fluid passageways 42 are grooved to receive sealing rings49.

Positioned between solenoid coils 16 and 36 as shown in FIGS. 1 and 2 isa permanent magnet whose opposing ends 62 and 64 are oriented betweenthe adjacent pole faces of the arms of cores 12 and 32. Circularopenings 63 and 65, shown in FIG. 3, are formed in ends 62 and 64. Thewalls 66 and 68 of permanent magnet 60, defined by circular openings 63and 65, entirely circumscribe a pair of poppet valves 70 and 72,respectively. Valves 70 and 72 are movable between valve-closed andvalveopened positions so as to control fluid flow. The valves areconstructed of suitable magnetizable material so they may also operateas armatures.

To securely connect together magnets 12, 32 and 60 and eliminate allrelative movement, referring again to FIG. 1, a pair of non-magneticsleeves 75 and 77 are provided. Oppositely facing arms 19 and 39 areinserted into the opposite ends of sleeve 75, an intermediate portion ofwhich fits against circular wall 66. Integrally formed on the interiorwall of sleeve 75 is an inwardly extending lip 76 which together withspherical wall 46 constitutes a valve seat 80 for ball 70. In a similarmanner, oppositely facing arms 21 and 41 are inserted into opposing endsof sleeve 77 while an intermediate portion of sleeve 77 fits againstcircular wall 68. Formed on the interior of sleeve 77 is an inwardlyextending lip 78 that along with spherical wall 47 constitutes a valveseat 82 for ball 72. The coaction of sleeves 75 and 77 serve to preventall relative movement between magnets 12, 32 and 60.

Circular walls 66 and 68 also function as pole faces. As shown in FIG.3, the magnetic flux lines bridging the annular gaps 63 and 65 betweenthe balls and adjacent circular pole faces are substantially evenlydistributed. One advantage of this arrangement is that during theirlifting and seating strokes, the balls will travel along substantiallystraight lines. If the pole faces did not circumscribe the balls, theywould tend to travel in olf-centered paths. The balls are magneticallyguided rather than mechanically guided by the circular pole faces. Bytraveling along substantially straight paths to and from their seats,the valve response time will be minimized and also the usual rolling andsliding motion experienced by the balls attempting to center themselveson their seats will also be minimized.

When balls 70 and 72 are moved through their lifting strokes to theirvalve-opened positions or through their seating strokes to theirvalve-closed positions, no components of assembly 10 other than balls 70and 72 are moved. By this inventive val-ve arrangement there is no needfor springs, mechanical guides, sliding fits, etc., which often arecomplex and increase the risk of valve failure. Valves 70 and 72 areurged to and from their seats under the influences of magnetic forcesgenerated by a magnetic circuit in which they operate as armatures. Themovements of balls 70 and 72 occur substantially simultaneously due tothe fact that they are magnetically interlinked in a common magneticcircuit in which the motion of one valve-armature influences the motionof the other valve-armature causing the valves to move substantiallysimultaneously. In this aspect of the invention, i.e., magneticallyinterlinking a plurality of valves, the valve assembly of this inventionis similar to the invention described in US. patent application Ser. No.641,031 filed on May 24, 1967 which invention has been assigned to theassignee of the instant invention.

As shown in FIG. 1, valves 70 and 72 are closed against their seats and82, and therefore fluid that has entered inlet tubes 85 and 87 isprevented from being discharged through outlet tubes 86 and 88,respectively. In this condition, neither solenoid coil 16 nor 36 isenergized. In order to understand how the magnetic circuit is utilizedto actuate balls 70 and 72, a magnetic loop constituted by core 12,permanent magnet 60 and balls 70 and 72 will be referred to as loop Ashown in FIG. 5. A second magnetic loop constituted by core 32,permanent magnet 60 and balls 70 and 72 will be referred to as loop B.Under electrically de-energized, valve-closed conditions, the magneticreluctance in loop A is greater than the reluctance in loop B, i.e.; themagnetic circuit permeance in loop B is greater than the permeance inloop A. This results in a greater magnetic flux density in the loop Bthan in loop A. The relative difference in flux density in loops A and Bis depicted schematically by three flux lines 0 in loop B and only oneflux line 0 in loop A. The resulting greater magnetic forces in loop Boperate to attract the balls holding them firmly against their sphericalseats.

In order to urge the 'balls through their lifting strokes to theirvalve-opened positions, coil 16 is energized so as to intensify themagnetic polarity differential between pole faces 28 and 29 and balls 70and 72, respectively. Simultaneously electrical coil 36 is energized todecay the magnetic polarity differential between pole faces 46 and 47and balls 70 and 72, respectively. At the point in time when theincreased magnetic force between pole face 28 and ball 70 exceeds both,(1) the decreased magnetic force between pole face 46 and ball 70, and(2) the unbalanced force generated by the pressure of fluid in reservoir31 operating on the areas of sealing ring 49, the lifting stroke of ball70 will be initiated.

The increase of magnetic polarity differential on the upper pole faces28 and 29 and the simultaneous decrease in polarity differential on thelower pole faces 46 and 47 causes permanent magnetic flux to bedeflected from loop B to loop A. The change is depicted by the changethat has occurred between FIG. 5 and FIG. 6. During the inductive laginterval from initial electrical energization to the start of ballmotion, the flux output from the permanent magnet is essentiallyconstant, and is simply being diverted from use in loop B andelectromagnet 32 to use in loop A and electromagnet 12. Because thepermanent magnet flux is constant during this energization period, thereis no flux change in gaps 63 and 65, shown in FIG. 3, and thence noelectrically supplied energy is wasted in these gaps. Therefore theinductive lag time is minimized for a given electrical power level. Thisalso permits the reluctance in these gaps to be relatively high, whichresults in minimum ball mass (for superior vibration, shock resistance,faster movement response) and maximum gap length which. increasescontamination tolerance of the valves. I

If for some reason, the forces on ball 70 are different than the forceson ball 72 so that after ball 70 commences its movement ball 72 remainsin place, then lagging ball 72 will commence its lifting stroke veryrapidly. This will occur automatically because the balls aremagnetically interlinked. In addition to different fluid pressures thatmay cause the motion of ball 70 to precede that of ball 72 other factorsaffecting this situation could be sticking, different manufacturingtolerances, etc. Movement of ball 72 will quickly commence because asthe gap between moving ball 70 and pole face 28 narrows, there isconcomitant decrease of magnetic reluctance in loop A, accompanied by anincrease in magnetic flux density urging the ball 72 to open. Also, asthe gap between moving ball 70 and pole face 46 widens, there is aconcomitant increase of magnetic reluctance in loop B, accompanied by adecrease in magnetic flux density tending to maintain the ball 72 in itsclosed position. Thus, if for one of the reasons outlined above, themotion of one ball should precede the other, the fact that they aremagnetically interlinked in the same magnetic circuit, will soon correctthis mismatch of motion and produce substantially simultaneous movement.

When coils 16 and 36 are de-energized, balls 70 and 72 will remain intheir valve-opened positions bearing against pole faces 28 and 29 due tothe fact that the magnetic reluctance in loop B will remain greater thanthat in loop A. This necessarily results because the gaps between theballs and their associated pole faces of loop A are approximately zeroor at least the gaps are substantially smaller than the gaps between theballs in their associated pole faces in loop B.

In accordance with this valve arrangement, the balls are returned fromtheir valve-opened to their valve-closed positions simply by energizingthe coils with electrical polarities opposite to that used to open thevalve. Thus, the electrical current in coil 16 is transmitted in theopposite direction so as to decay the polarity between pole faces 28 and29 and balls 70 and 72, respectively. Simultaneously, the electricalcurrent in coil 36 is transmitted in the opposite direction so as tointensify the polarity and hence magnetic attracting force between polefaces 46 and 47 with balls 70 and 72, respectively. Should the movementof one ball precede the movement of the other ball, then due to the factthat the balls are magnetically interlinked, they will be returned totheir valve-closed positions substantially simultaneously.

Valve assembly may be used in a broad variety of environments and is notlimited to any specific use. It may, for example, be used to achieve ahighly reliable and precise mixture of two different liquids such as afuel propellant entering inlet tube 85 and an oxidizer propellantentering inlet tube 87. With the balls in their valveopened positions,fuel propellant would be conducted successively through passageway 22,conically shaped port 23, annular passageway 24 and into reservoir 31.It should be noted that the liquid flow is uniformly distributed aroundthe ball, thereby tending to maintain the ball in a stable, centeredposition during valve opening and closing motion periods. The fueleventually flows outwardly through passageway 42 and is ultimatelydischarged through outlet tube 86. The flowing oxidizer stream isentirely segregated from the flowing fuel stream. Oxidizer enteringinlet tube 87 flows successively, in a continuous stream, throughpassageway 22, conically shaped port 23, annular passageway 24,reservoir 23, passageway 42 and ultimately outlet tube 88. It isimportant in many instances to maintain the fluids, whether or not theyare flowing, separated from one another. This is especially important inthe case where premature mingling of volatile fluids capable ofdeveloping a hypergolic reaction may occur. Unless safeguards are takencatastrophic ramifications could result in destroying the valve assembly10 and more important the structure in which it is incorporated.

Another embodiment of this invention shown in FIG.

4, is constructed so that the balls will maintain their valve-openedpositions only with electrical energization and automatically return totheir valve-closed positions when the electrical coils are de-energized.This is to be contrasted with the construction of the invention shown inFIG. 1 in which the balls remained in their valveopened positions uponde-energizing the coils. It should be noted that the valve assemblies ofFIGS. 1 and 4 are very similar and therefore many of the same numeralsare utilized to explain the construction and operation of the valveassembly depicted in FIG. 4. As shown, ball 70 is raised by the maximumdistance from its spherical seat 46. In its valve-opened position, ball70 rests against a shim or stop 91 which is connected to the pole face28 of plug 25. Shim 91 is constructed from any suitable nonmagnetizablematerial and is positioned such that when ball 70 is raised to itsvalve-opened position the distance AA between the ball and pole face 28will always exceed the distance AB between the ball and pole face 46.Therefore, when the electrical coils are de-energized, the magneticreluctance across gap AA will exceed the magnetic reluctance across gapAB. A direct consequence of this arrangement is that the magneticattracting force exerted by pole face 46 will exceed that exerted bypole face 28 and therefore will be suflicient to draw ball 70 back toits valve-closed position. There is no need to reverse the current flowthrough the coils to create a reverse polarity situation in order toreturn the balls to their valve-closed positions.

It should be noted that while this invention is characterized bysuperior advantages over conventional dual valve assemblies, theinvention may also be used to achieve superior results in controllingfluid flow through a single valve. In a single valve construction therewould be no need for magnetic interlinking.

Although particular embodiments have been chosen to illustrate thisinvention, it should be noted that the scope of this invention is to belimited only by the following claims.

I claim:

1. A multiple valve assembly for magnetically moving at least two valvesbetween valve-closed and valve-opened positions comprising:

a first electromagnet having two Pole faces,

a second electromagnet having two pole faces, the pole faces of thefirst and second electromagnets being positioned adjacent one another todefine a pair of spaces,

a permanent magnet disposed between the two electromagnets and extendingbetween said pair of spaces,

support structure for interconnecting the electromagnets and permanentmagnet,

a pair of valves made of magnetizable material disposed wtihin thespaces, and

a magnetic circuit including the valves, for diverting permanent magnetgenerated flux from one electromagnet to the other in order to move thevalves between their valve-closed and valve-opened positions.

2. The structure according to claim 1 wherein the magnetic circuitincludes a first magnetic loop constituted by the first electromagnet,the permanent magnet and the valves and a second magnetic loopconstituted by the second electromagnet, the permanent magnet and thevalves, and

the valves are magnetically interlinked for substantially simultaneousmovement.

3. The structure according to claim 2 wherein when the circuit isenergized the valves are moved from one position adjacent one loop totheir other position adjacent the other loop and when the circuit isde-energized, the valves remain in the other position, the valves beingreturned to their said one position by energizing and reversing thepolarity of the magnetic circuit.

4. The structure according to claim 3 wherein when the valves are intheir said other position and the circuit is de-energized the magneticreluctance in said one loop is greater than that in said other loop.

5. The structure according to claim 2 wherein when the circuit isenergized the valves are moved from one position adjacent one loop totheir other position adjacent the other loop and when the circuit isde-energized the valves automatically return to their said one position.

6. The structure according to claim 5 wherein when the valves are intheir said other position and the circuit is de-energized the magneticreluctance in said one loop is less than that in said other loop.

7. The structure according to claim 6 further comprising stopspositioned adjacent the pole faces associated with said other loop forpreventing the valves from being closer to these pole faces than thepole faces associated with said one loop.

8. The structure according to claim 1 further comprising a pair of fluidinlet passageways formed in one electromagnet communicating with thespaces,

a pair of outlet passageways formed in the other electromagnetcommunicating with the spaces,

wherein when the valves are in their valve-opened positions a pair ofseparated continuous flow lines are formed.

9. The structure according to claim 8 wherein each inlet passageway hasan annular port surrounding one pole face of said one electromagnet andeach outlet passageway passes through one pole face of the said otherelectromagnet.

10. The structure according to claim 1 wherein the electromagnets areC-shaped, opening towards one another and the support structure is apair of sleeves, the opposing ends of one sleeve receiving one set ofthe adjacent arms of the electromagnets while the other sleeve receivesthe other set of adjacent arms of the electromagnets.

11. The structure according to claim 8 wherein the valves are balls andthe permanent magnet is formed on its opposite ends with a pair ofcircular openings that encircle the balls and serve as pole faces so asto promote substantial straight line movement of the balls between theirpositions.

12. The structure according to claim 11 wherein the pole faces of theelectromagnets are spherically shaped and serve as valve seats topromote centering of the balls.

13. A valve assembly for magnetically moving a valve betweenvalve-closed and valve-opened positions comprising:

a first electromagnet having a pole face,

a second electromagnet having a pole face, the pole faces of the firstand second electromagnets forming at least one valve seat beingpositioned adjacent one another to define a space,

a permanent magnet disposed between the two electromagnets and aroundsaid space,

a valve made of magnetizable material disposed within the space, and

a. magnetic circuit including the valve for diverting permanent magnetgenerated flux from one electromagnet to the other in order to move andmagnetically guide the valve with respect to said valve seat between itsvalve-closed and valve-opened positions.

14. The structure according to claim 13 wherein:

the valve is a ball,

the pole faces of the electromagnets are spherically shaped and serve asvalve seats to promote centering of the ball, and

the permanent magnet is formed with a circular opening that encirclesthe ball and serves as a pole face so as to promote substantial straightline movement of the ball.

References Cited UNITED STATES PATENTS HENRY T. KLINKSIEK, PrimaryExaminer.

US. Cl. X.R.

